Glass device housings

ABSTRACT

An electronic device may have a glass housing structures. The glass housing structures may be used to cover a display and other internal electronic device components. The glass housing structure may have multiple glass pieces that are joined using a glass fusing process. A peripheral glass member may be fused along the edge of a planar glass member to enhance the thickness of the edge. A rounded edge feature may be formed by machining the thickened edge. Raised fused glass features may surround openings in the planar glass member. Multiple planar glass members may be fused together to form a five-sided box in which electronic components may be mounted. Raised support structure ribs may be formed by fusing glass structures to a planar glass member. Opaque masking material and colored glass may be used to create portions of the glass housing structures that hide internal device components from view.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation patent application of U.S. patentapplication Ser. No. 17/033,151, filed Sep. 25, 2020 and titled “GlassDevice Housings,” which is a continuation patent application of U.S.patent application Ser. No. 16/692,798, filed Nov. 22, 2019 and titled“Glass Device Housings,” now U.S. Pat. No. 10,842,031, which is acontinuation patent application of U.S. patent application Ser. No.16/138,933, filed Sep. 21, 2018 and titled “Glass Device Housings,” nowU.S. Pat. No. 10,512,176, which is a continuation patent application ofU.S. patent application Ser. No. 15/653,171, Jul. 18, 2017 and titled“Glass Device Housing,” now U.S. Pat. No. 10,278,294, which is acontinuation patent application of U.S. patent application Ser. No.14/819,110, filed Aug. 5, 2015 and titled “Glass Device Housing,” nowU.S. Pat. No. 9,756,739, which is a continuation patent application ofU.S. patent application Ser. No. 14/295,110, filed Jun. 3, 2014 andtitled “Fused Glass Device Housings,” now U.S. Pat. No. 9,125,298, whichis a continuation patent application of U.S. patent application Ser. No.13/358,389, filed Jan. 25, 2012 and titled “Fused Glass DeviceHousings,” now U.S. Pat. No. 8,773,848, the disclosures of which arehereby incorporated herein by reference in their entireties.

BACKGROUND

This relates to electronic devices and, more particularly, to glassstructures for electronic devices.

Electronic devices such as cellular telephones, handheld computers, andportable music players often include housings with glass members. Forexample, a device with a display may have a glass cover that serves as aprotective layer. In some devices, a rear housing surface may be formedfrom a layer of glass.

To ensure satisfactory robustness, it is generally desirable to formdevice housing structures such as cover glass layers and housingsurfaces from structures that are sufficiently strong to prevent damageduring accidental impact events. For example, it is generally desirableto form portable devices that are subject to drop events from structuresthat are able to withstand the forces involved in a typical drop eventwithout incurring excessive damage.

Glass strength and device aesthetics can sometimes be enhanced by usingsufficiently thick glass layers. However, the size and weight of adevice should not be excessive. If care is not taken, modifications thatare made to ensure that a device has glass structures that aresufficiently strong, will make the device heavy and bulky.

It would therefore be desirable to be able to provide improved glassstructures for electronic devices.

SUMMARY

An electronic device may have a glass housing structures. The glasshousing structures may be used to cover a display and other internalelectronic device components. The glass housing structures may cover afront face of an electronic device and, if desired, may cover additionaldevice surfaces.

The glass housing structure may have multiple glass pieces that arejoined using a glass fusing process. A peripheral glass member may befused along the edge of a planar glass member to enhance the thicknessof the edge. A rounded edge feature may be formed by machining thethickened edge. Raised fused glass features may surround openings in theplanar glass member. Raised support structure ribs may be formed byfusing glass structures to the planar glass member.

Multiple planar glass members may be fused together to form a five-sidedbox in which electronic components may be mounted. Display structuresand other internal components may be slid into place between opposingglass sides of the box.

Opaque masking material and colored glass may be used to create portionsof the glass housing structures that hide internal device componentsfrom view.

Further features of the invention, its nature and various advantageswill be more apparent from the accompanying drawings and the followingdetailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an illustrative electronic device with adisplay and a supporting stand in accordance with an embodiment of thepresent invention.

FIG. 2 is a perspective view of an illustrative electronic device suchas a tablet computer in accordance with an embodiment of the presentinvention.

FIG. 3 is a perspective view of an illustrative electronic device suchas a media player in accordance with an embodiment of the presentinvention.

FIG. 4 is a perspective view of an illustrative portable electronicdevice such as a cellular telephone or other handheld device inaccordance with an embodiment of the present invention.

FIG. 5 is a cross-sectional side view of an illustrative electronicdevice having a display formed from display structures that are receivedwithin a recess in covering glass structures in accordance with anembodiment of the present invention.

FIG. 6 is a cross-sectional side view of an illustrative electronicdevice having glass structures with thickened peripheral edges and acentral recess that have been mounted to a curved rear housing inaccordance with an embodiment of the present invention.

FIG. 7 is a cross-sectional side view of an illustrative electronicdevice having glass structures with thickened peripheral edges and acentral recess that have been mounted to mating rear glass housingstructures in accordance with an embodiment of the present invention.

FIG. 8 is a cross-sectional side view of an illustrative electronicdevice having glass structures with thickened peripheral edges and acentral recess that have been mounted mating rear glass housingstructures using an interposed housing member in accordance with anembodiment of the present invention.

FIG. 9 shows equipment and operations involved in forming glasselectronic device housing structures in accordance with an embodiment ofthe present invention.

FIG. 10 is a perspective view of an illustrative corner portion of aglass device housing structure in accordance with an embodiment of thepresent invention.

FIG. 11 is a perspective interior view of an illustrative planar glasshousing member with support structures that have been implemented byfusing ribs of glass to the planar glass housing member in accordancewith an embodiment of the present invention.

FIG. 12 is a perspective interior view of an illustrative planar glasshousing member with raised fused glass structures that surround aspeaker port opening and a button opening in the planar glass housingmember in accordance with an embodiment of the present invention.

FIG. 13 is a cross-sectional side view of an illustrative device showinghow glass housing structures in the device may be provided with raisedfused glass portions on an exterior surface surrounding an opening for abutton in accordance with an embodiment of the present invention.

FIG. 14 is a cross-sectional side view of glass structures formed fromby fusing a colored peripheral glass member to an edge portion of aplanar glass member in accordance with an embodiment of the presentinvention.

FIG. 15 is a cross-sectional side view of glass structures formed fromby fusing a peripheral glass member to an edge portion of a planar glassmember and covering the bottom and inner surfaces of the peripheralglass member with an opaque masking material in accordance with anembodiment of the present invention.

FIG. 16 is a cross-sectional side view of glass structures formed fromby fusing a peripheral glass member to an edge portion of a planar glassmember and covering the inner surface of the peripheral glass memberwith an opaque masking material in accordance with an embodiment of thepresent invention.

FIG. 17 is a cross-sectional side view of glass structures formed fromby fusing a colored peripheral glass member to an edge portion of acolored planar glass member in accordance with an embodiment of thepresent invention.

FIG. 18 is a cross-sectional side view of glass structures formed fromby fusing a peripheral glass member to an edge portion of a planar glassmember and coating the interior surface of the glass structures with anopaque masking material in accordance with an embodiment of the presentinvention.

FIG. 19 is a diagram showing how glass electronic device housingstructures may be provided with a rounded edge and a laminated flexibledisplay structure in accordance with an embodiment of the presentinvention.

FIG. 20 is a cross-sectional side view of glass structures formed fromby fusing a peripheral glass member with an angled edge to a planarglass member in accordance with an embodiment of the present invention.

FIG. 21 is a cross-sectional side view of glass structures formed fromby fusing a peripheral glass member with a curved edge to a planar glassmember in accordance with an embodiment of the present invention.

FIG. 22 is a diagram showing how an extruded glass structures for anelectronic device housing may be provided with a fused end cap inaccordance with an embodiment of the present invention.

FIG. 23 is a diagram showing how glass housing structures formed from afive-sided box of fused glass members may be provided with internalcomponents in accordance with an embodiment of the present invention.

FIG. 24 is a diagram showing how internal components may be slid into acavity within glass housing structures formed from a five-sided box offused glass members in accordance with an embodiment of the presentinvention.

FIG. 25 is a cross-sectional side view of illustrative five-sided boxglass fused glass structures that have been provided with internalcomponents and a rounded edge in accordance with an embodiment of thepresent invention.

FIG. 26 is a cross-sectional side view of glass structures formed byfusing a peripheral glass member to a planar glass member and configuredto be illuminated along an edge using a light source in accordance withan embodiment of the present invention.

FIG. 27 is a flow chart of illustrative steps involved in forming glasshousing structures in accordance with an embodiment of the presentinvention.

DETAILED DESCRIPTION

Electronic devices such as computers, handheld devices, computermonitors, televisions, cellular telephones, media players, and otherequipment may have displays and other components that are covered withglass structures. The glass structures, which may sometimes be referredto as glass housing structures, may be used to provide a protectivetransparent covering for a display or other optical component, may beused to form a housing sidewall, may be used to form other housingstructures such as a rear housing wall or other housing structures, maybe used to form raised features such as raised ribs that serve assupport structures for a sheet of glass or other glass structures, ormay otherwise be used in forming structures in an electronic device.

An example of an electronic device that may have glass housingstructures is shown in FIG. 1 . In the example of FIG. 1 , electronicdevice 10 has a stand such as stand 12 on which main unit 14 has beenmounted. Main unit 14 may include a display such as display 16 and arear housing such as rear housing 18 (as an example). Device 10 may be amonitor, a monitor with an integrated computer, a television, or otherelectronic equipment.

Housing 18 may be formed from metal, plastic, glass, ceramic,carbon-fiber composite material or other fiber-based compositematerials, other materials, or combinations of these materials. Display16 may be covered with glass structures 20. Glass structures 20 mayserve as a glass front housing structure for device 10. Glass structures20 may be transparent so that display 16 may be viewed by a user ofdevice 10 through glass structures 20. Display 16 may include displaystructures with image pixels formed from light-emitting diodes (LEDs),organic LEDs (OLEDs), plasma cells, electrowetting pixels,electrophoretic pixels, liquid crystal display (LCD) components, orother suitable image pixel structures. Touch sensor electrodes may beincluded in display 16 to provide display 16 with touch sensingcapabilities (e.g., display 16 may be a touch screen) or display 16 maybe touch insensitive.

In the illustrative example of FIG. 2 , device 10 is a portable devicesuch as a tablet computer, gaming device, navigation device, etc.Display 16 may be mounted in housing 18. Display 16 may be covered witha display cover layer formed from glass structures 20. Openings may beformed in glass structures 20 to accommodate components such as button22.

FIG. 3 is a perspective view of electronic device 10 in a configurationin which the electronic device housing has been formed from glassstructures 20 that surround internal device components. End face 20′ ofdevice 10 may also be formed from glass (as an example) and may includeopenings for audio jack 28, switch 30, and digital connector port 32 (asexamples). Display 16 may be used to display images on one or more sidesof device 10. The portion of glass structures 20 of FIG. 3 that overlapdisplay 16 may be transparent, so that the images displayed by display16 may be visible by a user of device 10 through glass structures 20.The rear surface of glass structures 20 may be transparent or may becolored (as examples).

In the illustrative example of FIG. 4 , device 10 has been provided withupper and lower glass layers 20. Housing structure 38 (e.g., a layer ofglass, ceramic, plastic, fiber-based composite, other material, orcombination of these materials) may optionally be interposed betweenupper and lower glass structures 20. Structures 20 and optionalstructure 38 may form a housing for device 10. Display 16 may be mountedbehind upper glass layer 20 (e.g., on the front face of device 10).Openings in glass structures 20 may be used to accommodate buttons suchas button 34 and other components (e.g., a speaker aligned with speakerport 36).

The illustrative device configurations of FIGS. 1, 2, 3, and 4 aremerely illustrative. Any suitable electronic equipment may be providedwith glass housing structures, if desired.

FIG. 5 is a cross-sectional side view of electronic device 10 in aconfiguration in which glass housing structure 20 has been used to forma cover glass layer over display structures 40. Display structures 40may be used to form display 16.

Display structures 40 may include a number of layers of material. Theselayers may include, for example, layers of glass, layers of plastic, andlayers of adhesive. A liquid crystal display may have layers ofpolarizer, light diffusing elements, light guides for backlightstructures, and a liquid crystal layer. An organic light-emitting diode(OLED) display may have organic materials that are used in producinglight. An array of circuit components such as a thin-film transistor(TFT) array may be used to drive the image pixels in a display. Thisarray of circuitry may be formed on a substrate material such as glassor polymer. The substrate layer on which the thin-film transistorsand/or other circuitry for the display are formed may sometimes referredto as a TFT substrate or transistor substrate.

Glass housing structures 20 may be mounted to housing structures 18(e.g., housing structures formed from metal, glass, plastic, fiber-basedcomposites, etc.). Internal components may be mounted within the housingof electronic device 10. For example, device 10 may include a printedcircuit such as printed circuit 42. Printed circuit 42 may be a rigidprinted circuit board (e.g., a fiberglass-filled epoxy board), aflexible printed circuit (“flex circuit”) formed from a flexible sheetof polyimide or other polymer layer, or may formed using otherdielectric substrate materials. Components 44 such as switches,connectors, discrete circuit elements such as capacitors, resistors, andinductors, integrated circuits, and other electronic devices may bemounted to substrate 42. Display structures 40 may be coupled tocircuitry on substrates such as substrate 42 using communications path46 (e.g., a flex circuit cable or other suitable path).

To help maximize the interior volume in device 10 and reduce the sizeand weight of glass structures 20, center portion 48 of glass structures20 may have a thickness T1 that is smaller than edge thickness T2. Thesmaller size of thickness T1 may create a recessed portion 50. Recess 50in center portion 48 may have a rectangular shape or other suitableshape and may be configured to receive internal components in device 10such as display structures 40. The larger size of edge thickness T2relative to center thickness T1 may help strengthen glass structure 20along its periphery to prevent damage in the event of an impact event.The larger size of the edges of glass structures 20 may also improvedevice aesthetics.

Glass structures 20 may have a rectangular periphery (e.g., glassstructures 20 may be formed from structures such as a planar sheethaving a rectangular outline when viewed from above) and center portion48 may form a rectangular recess within center of glass structures 20.In this type of configuration, thickened edge portions 49 may form arectangular ring that runs around the periphery of glass structure 20.If desired, glass structure 20 may have other shapes (e.g., oval,circular, square, shapes with curved edges and/or straight edges, etc.).The thickened edge portions of glass structures 20 may also be providedalong only part of the edges of glass structures 20, rather than theentire periphery of glass structures 20.

Housing structures such as structures 20 and 18 may be joined usinginterposed layers of adhesive, using fasteners, using interlockingengagement features such as snaps, or using other suitable attachmentmechanisms.

In the illustrative example of FIG. 6 , glass structures 20 (e.g., theupper portion of the device housing) may have a planar exterior surface52 and lower housing 18 (e.g., metal, glass, plastic, ceramic,fiber-based composites, etc.) may be have a curved exterior surface 54.A display or other structures may be mounted under the recessed portionof glass structures 20. Internal components 44 may be mounted in theinterior of the device.

FIG. 7 is an example in which device 10 has been provide with twosubstantially similar glass housing structures 20. Structures 20 may, asan example, have rectangular shapes with thinner (recessed) centerregions 48 and thickened edges 49. One or more displays and otherinternal components may be provided in device 10 of FIG. 7 .

As shown in FIG. 8 , device 10 may have a housing member such as housingsidewall structure 18 that is interposed between upper and lower glasshousing structures 20. Structure 18 may be formed from metal, glass,ceramic, plastic, fiber-based composite material, other materials, or acombination of these materials. Upper and lower glass housing structures20 in FIGS. 7 and 8 may have recessed portions (e.g., rectangularrecesses), as described in connection with FIG. 5 . Display structuresand other internal device components may be received within the recessesof structures 20 of FIGS. 7 and 8 .

Device structures such as glass structures 20 may be formed frommultiple pieces of glass that are fused together. Glass structures may,for example, be heated to an elevated temperature (e.g., about 800° C.)that is above the glass fusion temperature and that is below the glassworking temperature. Using a metal die or other glass fusing tool, theheated glass pieces may be pressed together. Glass structures that arefused together using this type of approach may have invisible or barelyvisible joint lines (i.e., the fused glass joints that are formed whenfusing a first glass member to a second glass member may be invisible orbarely visible to the naked eye).

Illustrative operations and equipment involved in forming glassstructures 20 with recessed portion are shown in FIG. 9 .

Initially, a portion of glass structures 20 such as planar glass member20A may be formed and polished using polishing tool 56. For example,both upper surface 58 and lower surface 60 of glass structures 20A maybe polished using tool 56. Polishing tool 56 may be used to performmechanical and/or chemical polishing processes. Glass structures 20A maybe formed from a glass sheet with a rectangular shape, a shape withcurved edges, a shape with straight edges, or a shape with a combinationof curved and straight edges.

Following polishing operations with tool 56, additional glass structuresmay be fused to glass structures 20A using heated press (fusing tool)62. In particular, upper press member 64 may be moved downwards indirection 66 while lower press member 68 is moved upwards in direction70 to press glass structures 20A and glass structures 20B together.During pressing, the temperature of glass structures 20A and 20B may bemaintained at an elevated temperature of about 800° C. (e.g., atemperature above the fusion temperature of the glass and below theworking temperature of the glass). This forms glass fusion bond 72between structures 20A and 20B and fuses structures 20A and 20B togetherto form glass structures 20.

Glass structures 20B may, for example, be a peripheral glass memberhaving the shape of a rectangular ring that runs around the periphery ofa rectangular version of glass structure 20A or may be a glass memberthat runs around part of the periphery of glass structure 20A (asexamples). The glass structures that are formed by fusing structures 20Bto structures 20A may have an edge thickness T2 and a thinner centralregion of thickness T1, as described in connection with FIG. 5 (as anexample). If desired, glass structures 20A and/or 20B may have othershapes (e.g., to form additional glass thickness around an opening inglass structure 20A, to form ribs or other supporting structures onglass structures 20A, to form a peripheral thickened edge portion arounda non-rectangular piece of glass, etc.).

Because lower surface 60 of glass structures 20A was polished by tool56, this surface may remain polished following fusion of glassstructures 20B to glass structures 20A.

Following formation of glass structures 20 using glass fusing tool 62,glass structures 20 may be strengthened. For example, glass structures20 may be strengthened using chemical strengthening tool 74. Chemicalstrengthening tool 74 may be used to immerse glass structures 20 in abath containing potassium nitrate (as an example). Glass structures 20may be free of glass frit at fusion joints 72, which may promotecompatibility with chemical strengthening treatments. Heat-basedtempering operations may also be performed to strengthen glassstructures 20, if desired.

Following strengthening of glass structures 20 with chemicalstrengthening tool 74, glass structures 20 may have polished uppersurface 58, polished lower surface 60, recessed central region 48 ofthickness T1, and thickened edge regions 49 of thickness T2 (T2>T1).Glass structures 20 may then be assembled into device 10. For example,glass structures 20 may be attached to additional glass structures(using glass fusing, using adhesive, using fasteners, using matingengagement structures, etc.) and/or non-glass housing structures.

As shown in FIG. 10 , for example, glass structures 20 may be mounted tohousing structures 18. Because of the use of the glass fusing process ofFIG. 9 to join glass structures 20B to glass structures 20A, fusionjoint 72 between structures 20A and 20B may be invisible or nearlyinvisible to the naked eye of the user of device 10, thereby enhancingdevice aesthetics. The enhanced thickness T2 of the edge portion ofglass structures 20 (in the example of FIG. 10 ) may help improve theresistance of glass structures 20 to damage due to an impact event.

If desired, glass structures 20B may be fused to glass structures 20A inother patterns. For example, glass structures 20B that have the shape ofstrengthening support ribs may be fused across the center of the surfaceof glass structures 20A, as shown in FIG. 11 . Strengthening featuresformed from structures 20B may have the shape of a cross (as shown inthe example of FIG. 11 ), may have a T shape, may have a central armwith multiple branches, or may have any other suitable pattern. Thestrengthening structure pattern formed by glass structures 20B onstructures 20A of FIG. 11 is merely illustrative.

FIG. 12 is an interior perspective view of illustrative glass structures20 that have been provided with openings such as button opening 78(e.g., for button 34 of FIG. 4 ) and speaker port opening 76 (e.g., forspeaker port 36 of FIG. 4 ). As shown in FIG. 12 , glass structures 20Bmay be used to locally thicken glass structures 20A in the vicinity ofone or more openings in glass structures 20A. Glass structures 20B may,for example, form raised rings or other raised structures that surroundopenings 36 and 34 to provided additional structural support for glassstructures 20A in the vicinity of openings 36 and 34.

FIG. 13 is an illustrative cross-sectional side view of device 10 in aconfiguration in which glass structures 20 have been provided withexternal features by fusing glass structures 20B to upper surface 58 ofglass structures 20A. In the example of FIG. 13 , glass structures 20Bhave been used to create a raised feature such as a circular ring on thesurface of glass structures 20A that surrounds button 34. Light source80 may optionally be used to provide illumination for the raised ringformed by structures 20B. If desired, raised features may be formedelsewhere on surface 58 of glass structures 20A (e.g., surroundingspeaker port 36, in a particular location on a touch screen, around therectangular peripheral edge of display 16 and device 10, etc.).

Glass structures 20 may be formed from clear glass, glass with a coloredtint (e.g., a blue tint, red tint, green tint, etc.), black glass, grayglass, or glass of other colors. As shown in FIG. 14 , glass structures20A and 20B may be formed from glass of different colors. For example,glass structures 20A may be formed from clear glass and glass structures20B may be formed from black glass or non-clear glass of another color.The amount of color in structures 20B may be sufficient to renderstructures 20B dark or opaque in appearance or may allow structures 20Bto remain transparent. The use of a color for structures 20B that is notclear may help hide interior device components from view through theedge of structures 20.

As shown in FIG. 15 , internal device structures may also be hidden fromview by providing structures 20B with a layer of opaque masking material82. Material 82 may be black ink, white ink, colored ink, or otheropaque substances (as an example).

FIG. 16 shows how opaque masking material 82 may be formed on the inneredges of glass structures 20B. This may allow surfaces 84 of structures20B to remain uncovered so that surfaces 84 may be attached to devicestructures using adhesive (as an example).

FIG. 17 is a cross-sectional side view of glass structures 20 in aconfiguration in which glass structures 20A and glass structures 20Bhave both been formed from non-clear glass (e.g., black glass, grayglass, blue glass, green glass, other colored glass, etc.).

In the FIG. 18 example, glass structures 20 have been provided with alayer of opaque masking material 82 (e.g., black ink, white ink, coloredink, or other opaque substance) that covers lower surface 60 of glassstructures 20A and lower surfaces 84 of glass structures 20B.

Illustrative operations involved in forming glass structures 20 with arecessed portion and curved features such as rounded edges are shown inFIG. 19 .

As shown in FIG. 19 , a portion of glass structures 20 such as polishedplanar glass member 20A may be fused with glass structures 20B by movingstructures 20A in direction 66 while moving structures 20B in direction70 while applying heat in fusing tool (heated press) 62.

After fusing structures 20A and 20B together using tool 62, tool 92(e.g., a machining tool, grinding tool, polishing tool and/or otherequipment for machining and polishing structures 20) may be used inremoving excess glass along curved surfaces 86 and 88, thereby roundingthe edges of glass structures 20.

Glass strengthening equipment such as chemical strengthening tool 74 maybe used to strengthen glass structures 20 following formation of curvedsurfaces 86 and 88.

If desired, display structures 40 (FIG. 5 ) may be laminated to glassstructures 20 using lamination tool 90. For example, display 16 may belaminated to lower planar polished surface 60 and curved interiorsurface 88 of glass structures 20 using adhesive. Display structures 40may be formed using a substrate that is sufficiently flexible to allowdisplay structures 40 to conform to the curved shape of surface 88.Display structures 40 may be for example, flexible structures for aflexible liquid crystal display, flexible electrowetting displaystructures, flexible electrophoretic display structures, or flexibleorganic light-emitting diode display structures (as examples).

As shown in FIG. 20 , glass structures 20B may be provided with angled(beveled) inner edge surface 94. Surface 94 may be coated with anoptional opaque masking material such as layer 82. The non-zero anglethat is made by surface 94 with respect to surface normal 96 of planarlower surface 60 of planar glass member 20A may help improve thestrength of glass structures 20.

In the FIG. 20 configuration, the inner edge of glass structures 20B hasbeen provided with a planar surface (i.e., surface 94 is flat). Anillustrative arrangement in which the inner edge of glass structures 20Bhas been provided with a curved surface (curved surface 94) is shown inFIG. 21 .

FIG. 22 shows how glass structures 20 may be formed from extruded glassstructures such as extruded hollow-rod-shaped glass structure 20C andassociated cap structures such as end cap glass structure 20D. Glassstructures 20C and 20D may be formed using glass extruding and machiningtools such as tools 100. Fusing tool 62 may be used to fuse structures20C and 20D together. If desired, electronic component may be housedwithin the interior of extruded glass structures 20D. Fused caps 20C maybe used to enclose these internal components within the interior ofdevice 10.

FIG. 23 shows how internal electronic device components 102 may beinserted into glass structures 20E and, if desired, may be covered withfused end cap 20F. Structures 20E may be formed by fusing together fiveglass members to form a five-sided box with a lower face that is open toreceive components 102. The five-sided box may be formed from a firstpair of opposing planar structures (e.g., front and rear sheets ofglass), a second pair of opposing planar structures (e.g., opposing leftand right sheets or strips of glass), and a fifth planar sheet (orstrip) of glass such as end cap layer 20F that have been fused togetherusing fused joints. An air gap may be formed between opposing glasswalls in box-shaped glass structures 20E. Ribs or other strengtheningstructures such as structures 20B of FIG. 11 may be formed on one, two,three, four, or more than four of the surfaces of the five-sidedbox-shaped glass structures 20E of FIG. 23 .

Components 102 may be inserted into the interior of structures 20E(e.g., in the gap formed between the opposing front and rear sheets andbetween the opposing right and left sheets of glass). Components 102 mayinclude, for example, display structures 40 for forming display 16 andother components (see, e.g., components 44 of FIG. 5 ). Glass structures20E may be formed from sheets of glass that are fused together usingfusing equipment such as fusing tool 62 (FIGS. 9 and 22 ). Glassstructures 20F may be attached to glass structures 20E using glassfusing techniques, using adhesive, or using other attachment mechanisms.

FIG. 24 is a side view of glass structures 20E showing how internalcomponents 102 may be slid into the interior of glass structure 20E indirection 106 through end face opening 104 in glass structures 20E. Ifdesired, machining techniques such as the curved edge machiningtechniques described in connection with FIG. 19 may be used in creatingcurved surfaces on glass structures 20E (see, e.g., rounded edgesurfaces 108 of glass structures 20 of device 10 in FIG. 25 ).

As shown in FIG. 26 , edge 116 of glass structures 20 may be providedwith a roughened surface that helps to scatter and diffuse light. Device10 may be provided with a light-emitting diode or other internal lightsource 112. Light source 112 may produce light 114 that strikesroughened edge surface 116 of glass structures 20. Light 114 mayilluminate the exposed exterior edge of glass structures 20. Some or allof the peripheral edge portions of glass structures 20 may beilluminated in this way.

FIG. 27 is a flow chart of illustrative steps that may be used informing glass structures 20.

At step 118, glass structures such as glass structures 20A and 20B maybe polished using polishing equipment 56.

At step 120, fusing equipment 62 may be used to fuse two or more glassstructures together. For example, glass structures 20A and 20B may befused together to form glass structures 20 or the five sides of thefive-sided-box glass structures of FIGS. 23 and 24 may be fusedtogether.

If desired, additional machining and polishing operations may be formedat step 122. For example, a thickened edge portion (of thickness T2) ofglass structures 20 may be machined and polished to form a rounded edgefor glass structures 20, as shown in FIG. 19 . If desired, machiningoperations to form a rounded edge structure on glass structures 20 maybe performed during the operations of step 118 (e.g., using machiningand polishing equipment).

At step 124, glass structures 20 may be strengthened using heat and/orchemical treatment. For example, glass structures 20 may be strengthenedby applying a chemical bath to glass structures 20 using chemicalstrengthening tool 74.

At step 126, glass structures 20 may be assembled with other housingstructures to form electronic device 10. Glass structures 20 may, forexample, be attached to glass or non-glass housing structures 18 orother structures to form device 10. Internal components such as adisplay, integrated circuits, and other components may be mounted withinthe glass structures and other structures for the housing of device 10.

The foregoing is merely illustrative of the principles of this inventionand various modifications can be made by those skilled in the artwithout departing from the scope and spirit of the invention.

What is claimed is:
 1. A portable electronic device comprising: adisplay; electronic circuitry operably coupled to the display; and ahousing enclosing the display and the electronic circuitry, the housingcomprising: a first glass structure having a front wall having a firstthickness and defining a flat front external surface positioned over thedisplay, a first side wall having a second thickness greater than thefirst thickness and defining a first side external surface, and a frontedge defined by the flat front external surface and the first sideexternal surface; and a second glass structure having a rear walldefining a rear external surface opposite to the flat front externalsurface and a second side wall defining a second side external surfacethat extends from the rear external surface to the first side externalsurface, the second side external surface defining a continuous curvedprofile of the housing.
 2. The portable electronic device of claim 1,further comprising a speaker positioned within the housing, wherein: thefirst glass structure defines an opening within the flat front externalsurface; and the opening is aligned with the speaker.
 3. The portableelectronic device of claim 1, further comprising a button, wherein: thefront wall of the first glass structure defines a button opening; andthe button is positioned at least partially within the button opening.4. The portable electronic device of claim 1, wherein: the first glassstructure comprises: a front glass structure that defines the flat frontexternal surface; and a middle glass structure that defines the firstside external surface.
 5. The portable electronic device of claim 4,wherein the front glass structure is fusion bonded to the middle glassstructure.
 6. The portable electronic device of claim 1, wherein thefirst side external surface and the second side external surface definea continuous external profile of the housing.
 7. The portable electronicdevice of claim 1, further comprising a touch sensor positioned betweenthe display and the front wall of the first glass structure.
 8. Theportable electronic device of claim 1, wherein the display comprises atouch sensor.
 9. A tablet device comprising: a display; and a housingcomprising: a first glass structure having a front wall positioned overthe display and having a first thickness, a first side wall positionedat a side of the display and having a second thickness greater than thefirst thickness; and a second glass structure having a rear wallpositioned below the display and a second side wall, the second glassstructure defining a continuous curved profile of the housing.
 10. Thetablet device of claim 9, wherein: the first glass structure and thesecond glass structure meet at a seam located between an end of thefirst side wall and end of the second side wall; and a distance from thefront wall to the end of the first side wall is less than a distancefrom the rear wall to the end of the second side wall.
 11. The tabletdevice of claim 9, wherein the first glass structure is fusion bonded tothe second glass structure.
 12. The tablet device of claim 9, wherein:the front wall defining a flat front surface; the first side walldefines a flat side surface; and the first glass structure furtherdefines a front edge at a transition between the flat front surface andthe flat side surface.
 13. The tablet device of claim 9, wherein thedisplay is a touch sensitive display.
 14. The tablet device of claim 9,wherein: the first glass structure defines a curved internal surface ata transition between the front wall and the first side wall; and thedisplay is positioned along the curved internal surface.
 15. A portableelectronic device comprising: a display; and a housing enclosing thedisplay and comprising: a first glass structure defining a front portionand a first side portion of an external surface of the housing, thefront portion positioned over the display; and a second glass structuredefining a rear portion and a curved second side portion of the externalsurface of the housing, the curved second side portion extending fromthe rear portion to a seam between an intermediate structure and thesecond glass structure; and the intermediate structure between the firstglass structure and the second glass structure and defining a third sideportion of the external surface of the housing.
 16. The portableelectronic device of claim 15, wherein the intermediate structure is athird glass structure.
 17. The portable electronic device of claim 16,wherein the first side portion, the curved second side portion, and thethird side portion of the external surface of the housing togetherdefine a continuous region of an external surface of the portableelectronic device.
 18. The portable electronic device of claim 15,wherein: the front portion of the external surface of the housing isflat; and the first glass structure further defines an edge portion ofthe external surface of the housing, the edge portion extending betweenthe flat front portion and the first side portion of the externalsurface of the housing.
 19. The portable electronic device of claim 15,wherein the first glass structure further defines a curved internalsurface.
 20. The portable electronic device of claim 19, wherein thedisplay is bonded to the curved internal surface.